Preparation and application of immunoaffinity column coupled with dcELISA detection for aflatoxins in eight grain foods

This paper described a reliable and simple analytical method for the determination of aflatoxins (AFB₁, AFB₂, AFG₁, AFG₂) in cereals, peanuts, vegetable oils and fermented foods like beer, soybean sauce and soybean paste based on immunoaffinity column (IAC) cleanup coupled with direct competitive enzyme-linked immunosorbent assay (dcELISA) detection and confirmed by ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Under the optimized conditions, the home-made IAC capacity was 293, 60, 220 and 45 ng/mL gel for AFB₁, AFB₂, AFG₁ and AFG₂, respectively. Eight grain foods were pretreated with IAC, and then the extracts were detected by the dcELISA. The results showed that the recoveries of IAC-dcELISA ranged from 71.5% to 119.8% (relative standard deviations ≤ 16.67%) that were higher than dcELISA without IAC cleanup procedure by at least 30% on average, indicating that the matrix interference of different samples could be alleviated via the pretreatment of IAC, especially for fermented foods. The developed method was also confirmed by UHPLC-MS/MS with electrospray interface in positive mode using multiple reaction monitoring. In conclusion, this assay could be used as an effective analytical method for the determination of aflatoxins in complex grain foods.     

热态下鼓泡浆液反应器的气含率研究

本文在热态条件下，研究了鼓泡浆液反应器的气含率、反应器直径为0.098m，物系组成为氮气－液体石腊－石英砂。考察了气速、压力、温度、静床高及固体引入等因素对气含率的影响。对于53μm粒子的三相浆态体系，气含率与表观气速关系式为εG=0.053uG^1.2。     

连续式双膜分离塔的数学模型

本文建立了适用于连续式双膜分离塔的数学模型。用实验数据验证了数学模型的可行性和合理性。将本模型与已发表的模型进行了比较,结果表明本模型具有形式简单、计算方便和适用范围更宽广等优点。     

HEAT-TRANSFER AND GAS-HOLDUP STUDIES IN A BUBBLE COLUMN: AIR-WATER-GLASS BEAD SYSTEM

Air-holdup and heat-transfer coefficient values are measured in a 0.305 m diameter bubble column equipped with a seven-tube bundle for the air-water and air-water-glass bead system. The dependence of these two properties on air velocity (up to 0.28 m/s), temperature (297-343 K), glass bead powder average size (50-143.3 μm), solids concentration in the slurry (up to 20 weight percent) and bubble column diameter (0.108 and 0.305 m), is experimentally investigated. The effect of internals, as simulated by a single probe and a seven-tube bundle, in the two bubble columns is also examined. The models and correlations commonly employed to estimate these properties are assessed on the basis of generated data.     

Interval-graph-based PLA folding

In this paper we present algorithms to implement PLA folding based on the interval graph theory. A PLA will be represented by five sets of nets: product-term nets (PT nets), input and output nets (I and O nets), and input and output connection nets (IC and OC nets). Column folding becomes a problem of permuting the rows such that the I/O nets can be placed in as few columns as possible. Algorithms for both unconstrained and constrained foldings are given.     

浅谈PKPM框架结构设计注意事项

本文主要讲述在PKPM框架结构设计中注意的几个事项。从结构设计总说明各层布置图到基础平面图及详图几方面讲述。     

砖混结构房屋施工中容易发生的问题及解决对策

砖混结构是指小部分钢筋混凝土及大部分砖墙承重的结构。在砖混结构中加入构造柱和圈梁,能提高结构的抗震能力,但由于一些施工管理人员对构造柱的作用原理认识不清,施工中出现很多质量问题,使有些部位的构造柱和圈梁不但达不到抗震目的,反而影响了结构安全性。     

加强抗震观念 减轻地震灾害

本文根据唐山地震及汶川地震的震害分析,结合《建筑抗震设计规范》(GB 50011-2001 2008年版)提出抗震设计时应注意的几点看法。呼吁全社会加强抗震观念,从而减轻地震灾害。     

7°抗震设防区建八层以上砖砌体住宅的探讨

通过分析 7o抗震区砖砌体房屋的抗震性能及《规范》对其高度和层数的限制原因 ,指出配筋砌体是提高房屋抗震性能的有效措施 ,也是突破《规范》规定的方向所在。